geo 321 spring 2006 name class standing major (dept. or...

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Please fill out this information on the index cardGeo 321 Spring 2006

Name Class standing Major (dept. or div)

E-mail address Local phone # (optional)

Why are you here? (be honest)

"Special concerns"

Geology classes taken: by number

Geography classes taken: by number

Related science classes taken: by name

GEO 321 Crew• J. Steven Kite

–Office Hours: Th Th 11:30-12, 4-4:30–222/223 White–293-5603 x 4330

• Matt Finkenbinder TA–Office Hours: M W 9-10:30317 White–293-5603 x 4330 (Good Luck!)

General Systems Theory

System: A collection of related objects and the processes relating these objects.

Most geomorphic systems are open.

Steady state: (type of open system) balance between input and out flow.

Grade: Balance between driving forces and resisting forces

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Geomorphic Thresholds

Small input produces a change in equilibrium conditions w/in a geomorphic system

Equilibrium States

Time Scales & Geomorphology

New Topic:

TECTONICGEOMORPHOLOGY

Tectonic Geomorphologyvs.

Structural Geomorphology

Late Cenozoic Tectonic Movement vs.

Late Cenozoic Erosion of Older Structures

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Bloom Ch. 3: Cenozoic TectonicsAlso Review Your Geology 101Notes

Erosion Begins with Tectonic EventHybrid Tectonic-Structural Landforms

Old Ideas:

Tectonism Controlled by Internal Forces, Independent of Surface Processes.

Tectonism Controls TopographyTopography Determines Local

Climate

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New Ideas:

Climate Controls Surface ProcessesSurface Processes Control Rate of

UnroofingRate of Unroofing Determines

Isostatic ReboundIsostacy Is Important Component of

TectonismSo Climate Controls Tectonism, too

Live Folds: Zagros Mtns, Iran

http://www.peakware.com/encyclopedia/ranges/maps/zagros.htm(Also See Atlas of Landforms, p. 30, 152)

Short, N. M., and Blair, R. W., 1986, Geomorphology from Space, NASA daac.gsfc.nasa.gov/DAAC_DOCS/geomorphology/

GEO_2/GEO_PLATE_T-42.HTML

Anticline, Zagros Mtns

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Live Anticline, Breached by Water Gap

Live Folds -Consequent Drainage


GEO_2/GEO_PLATE_T-42.HTML

Zagros Mountains

Short, N. M., and Blair, R. W., 1986, Geomorphology

from Space, NASA

daac.gsfc.nasa.gov/DAAC_DOCS/

geomorphology/GEO_2/GEO_PLATE_T-

42.HTML

Zagros Mountains(Image Inverted)

Short, N. M., and Blair, R. W., 1986, Geomorphology

from Space, NASA

daac.gsfc.nasa.gov/DAAC_DOCS/

geomorphology/GEO_2/GEO_PLATE_T-

42.HTML

N

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Structural GeomorphologyExhumed Folds -Subsequent Drainage Synthetic

Aperature Radar(SAR) Image

Structural Landscape, Near

Harrisburg, Pennsylvania

Hom

oclinal, Anticlinaland

Synclinal Ridges, Pennsylvania

Short, N. M., and Blair, R. W., 1986

Gre

at V

alle

y

“Blu

e R

idge

”

Ridg

e &

Val

ley

Alle

hghe

nyFr

ont

Alle

hghe

nyM

tns

Sideling Hill, MD-WV-PA, Synclinal Ridge

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Wills Mountain (Breached) Anticline

Dolls Gap in Saddle Mountain

Greenland Gap

Seneca Rocks

Tuscarora Sandstone

OmOj

Oj

OmOj

OjOm

A AA

A =Anticline

S =Syncline


S

S

S

S

SA

Homoclinal, Anticlinal & Synclinal Ridges, near Altoona, Pennsylvania

N

8

Detail near Altoona, PennsylvaniaN

Homoclinal Ridges, near Rawlings, Wyoming


Syncline

Anticline

Anti-dip Side of Hogbacks, Flinders Range, Australia


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Dip Slope of Flatirons, Flinders Range, Australia

Richât Structure, MauritaniaSurface Expression of a Dome

http://daac.gsfc.nasa.gov/DAAC_DOCS/geomorphology/GEO_2/GEO_PLATE_T-31.HTML

Beds dip away from center.

Note Fractures.

TEC

TON

ICG

EOM

OR

PHO

LOG

Y:FA

ULT

S

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Earthquakes & Faults

• Stress: Force Applied• Strain: Response to Force

Fault

Plane of Weakness Along Which Movement Has Occurred

Active Fault1 Quake in 10,000 Y or 2 in 0.5 My

JointBreak Without Significant Movement

Types of FaultsStrike-Slip

Left-LateralRight-LateralTransform

Dip Slip NormalReverse

ThrustHinge Fault

Oblique-Slip

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Strike-Slip Motion

Lateral Fault

Strike-SlipSan Andreas

Fault

Photo byG.K. Gilbert

1906

Right-Lateral Fault

• Map View - Before

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Right-Lateral Fault

• Map View - After

Left-Lateral Fault

• Before After

Off

set

S tre

am C

hann

el, S

a n A

ndre

as F

ault

, Cen

tra l

Ca Which Type of Lateral Fault?

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Dip-Slip Motion

Fault Parts

Reverse Fault

Before

After

Stress

Compression= Squeezing

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Thrust Fault, Eastern

Pennsylvania

Thrust Fault Before Erosion

AutocthonAutocthon

AllocthonAllocthon (Thrust Sheet)(Thrust Sheet)Thrust FaultThrust Fault

Thrust Fault After Erosion

Fenster

Klippe

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Geologic Map: Thrust Fault After Erosion

FensterKlippe

Thrust Fault After Erosion

Fenster

Klippe

Fault-Line Scarps (= Exhumed Faults)

Scarp = Escarpment

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Klippe, Chief Mountain, Montana

www.smithsonianmag.si.edu/smithsonian/issues97/jul97/chiefmountain_jpg.html

Are Fensters, Klippen & Fault-Line Scarps

Tectonic or Structural Landforms?

Structural!

Normal Fault

Before

After

Stress

Tension = Pull-Apart

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Tension Normal FaultNormal Fault

Normal FaultNormal FaultTension

Oblique Fault

Before

After

Stress

Tension +Shear

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Two Tectonic Styles in Normally Faulted Landscape

Tilt-Block Mountains & Fault-Angle Valleys

Horst Horst

Graben Graben

Detail ofBasin & Range,

Colorado Plateau

NV, UT, AZ

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Sinai Peninsula

Dead Sea R

ift-Gulf of Aqaba

Gulf of Suez

Red Sea

Graben, Death Valley, CA

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Cycles of Fan and Pediment Genesis

GrabenFault block mtn. alluvial fan, pediment, basin, playa, fault block mtn.

Erosion Erosion

DepositionalBasin

Playa Lake

Telescope Peak, Mojave Desert

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Playa

Lake

Playa

“Salt Flat”

Salt Pan, Death Valley

Source: www.uoregon.edu/~millerm/ 5SP-13.jpeg

Martin Miller Photo

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Mountain Front

Mountain Front

Alluvial Fan Pediment

After Some Faulting& Erosion

Alluvial Fan, Death Valley, California

Source: www.uoregon.edu/~millerm/Dvfan.jpeg

Martin Miller Photo

Faulted Alluvial Fan, Panamint Range,Death Valley, California

Source: www.uoregon.edu/~millerm/5han.jpeg

Martin Miller Photo

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Alluvial Fan

Playa Dune Field

Mountain Front

Alluvial Fan

Bajada

Bajada

Turpan Depression, China

Alluvial Fan

Alluvial Fan Pediment

After More Faulting& Erosion

Mountain Front

Mountain Front

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Inselberg, Mojave Desert, near Baker, California

Photo: John F. McCauley, USGS

Two Egyptian Inselbergs

Granite Bedrock Sandstone BedrockCarol S. Breed, U.S.G.S.John F. McCauley, U.S.G.S.

Mountain-front sinuosity (S)

from Bull and McFadden (1975) paper

distance along mtn frontS =

distance between points

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Mountain-Front Sinuosity (S)

Basin

Mountain Front @ Fault

Mountains


Basin

New Mountain Front

Mountains

Old Mountain Front & Fault


Mountainsdistance along

mtn. front

distance betw.points

S =

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Mountain-Front Sinuosity (S) Increases w/ Time

distance along mtn. front

distance betw.points

S =

Mtn

s

New

est

Mtn

Fron

t

Inselbergs

Caracas, Venezuela, Revisited

Bottle Neck Valleys

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Triangular Facets or Flatirons

Humid, Faulted Landscapes (No Big Alluvial Fans! Why?)

Lineaments (Photolinears)

Produced by Weathered Rock-Fractures, Joints, Breccia,

Mylonites, Fault Gouge, etc.

Or by Resistant Rock Mineralization (e.g. Geothite)

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San Andreas

Fault

Lineament (Photolinear)

North Anatolian Transform Fault, Turkey

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VerkhoyanskiyOrogenic Belt,

Siberia

http://daac.gsfc.nasa.gov/DAAC_DOCS/geomorphology/GEO_2/GEO_PLATE_

T-29.HTML

FAULTS:

Most earthquake damage is related to landslides or structural failure because of surface waves.

Earth seldom opens up and swallows houses, people, cities, etc., but there are accounts of dogs, cows "lost", one guy had his leg trapped

Expected Earthquake Intensity

See Bloom, 2004,Figure 3-7

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Eastern US Neotectonics

Uplift (+) & Subsidence (-)

mm/yr = m/1000 yr

Source: Bloom, 2004 after Olliver & Brown 1976

uplift

uplift uplift

subsidencesubsidence

subsidence

New Image in 2007

NeotectonicsStable Areas

= Not So StableEvidence:

Differential Regional UpliftAppalachian Denudation = 20-120 mm/1000 ySurveying: Parts of Appalachians have Risen

6000 mm/1000 Y vs. East Coast. Uplift in Last 25 My > Uplift betw. 175-25 My

Warping of Coastal Plain Seds adjacent to Southern Appalachians

Mud Volcano (Diapir)Associated w/ Earthquakes

geo 321 spring 2006 name class standing major (dept. or...

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